Server: Active Directory

A boot loader is a file that contains necessary information that instruct the system how to boot/start an operating system.
Windows 7 and Vista bootloader file is \bootmgr
Windows XP bootloader file is \ntldr

C:/>bcdedit /set safeboot dsrepair (or Press F8)

C:/>bcdedit /deletevalue safeboot


NOTE: The example below uses F: as the Windows XP partition

bcdedit /create {ntldr} /d "Windows XP"

bcdedit /set {ntldr} device partition=F:

bcdedit /set {ntldr} path \ntldr

bcdedit /displayorder {ntldr} /addlast